The CFAR Clinical Core comprises three components, namely the Special Immunology Unit (SIU), the SIU Data Base and the AIDS Clinical Trials Unit (ACTU). The SIU is the largest HIV clinical in Northern Ohio and one of the largest in the midwest. Through close coordination with the CFAR- supported SIU Data Base and the ACTU, the SIU provides state-of-the-art care to approximately 650 persons with HIV-1 disease without regard to ability to pay and thus its patient population is representative of the communities we serve. The SIU Data Base is a novel, interactive, three dimensional data base developed at the CWRU CFAR containing complete laboratory, clinical and treatment information on 1162 patients who received or have received their HIV care at the SIV. This data base is an invaluable resource for clinical care, for identifying patients eligible for clinical trials and clinical research projects, for quality assurance and for epidemiologic studies. The SIU specimen repository, which was developed with CFAR funds, and is fully integrated with the SIU database contains more than 13,000 sets of frozen plasmas and cells obtained from SIU patients that can be used for selected retrospective laboratory analyses. The CWRU ACTU is a highly ranked member of the NIH-funded ACTG network that has enrolled over 1200 patients into AIDS treatment trials since its inception in 1987. This unit has particular expertise and interest in immune-based and host-directed therapies and utilizing the HIV treatment trial as a means to examine critical questions of disease pathogenesis. The ACTG Immunology Advanced Technology Laboratory (ATL) and SIU Specimen repository capitalize on the expertise and resources of the national network of 16 Immunology ATLs to bring standardized immunologic monitoring to AIDS treatment trials and clinical studies. Together these CFAR Core resources provide an infrastructure that facilitates clinical and translational research activities at the CWRU CFAR. Specific (H.J. Kung, CA46613); Characterization of HIV-1 protease mutations in personal failing Protease inhibitor-containing treatment regimens (J. Leis, CA 52047; Comparison of LTR sequence heterogeneity in plasma and in peripheral blood lymphocytes (E.J. Arts, AI36219); Validation of urine and plasma detection of mycobacterial antigen for the diagnosis disseminated MAC disease (R. Wallis, AI24298).